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. 1999 Oct;8(10):2019–2026. doi: 10.1110/ps.8.10.2019

Structure and function of the N-linked glycans of HBP/CAP37/azurocidin: crystal structure determination and biological characterization of nonglycosylated HBP.

L F Iversen 1, J S Kastrup 1, S E Bjørn 1, F C Wiberg 1, I K Larsen 1, H J Flodgaard 1, P B Rasmussen 1
PMCID: PMC2144139  PMID: 10548047

Abstract

The three N-glycosylation sites of human heparin binding protein (HBP) have been mutated to produce a nonglycosylated HBP (ng-HBP) mutant. ng-HBP has been crystallized and tested for biological activity. Complete X-ray data have been collected to 2.1 A resolution, and the structure has been fully refined to an R-factor of 18.4% (R(free) 27.7%). The ng-HBP structure reveals that neither the secondary nor tertiary structure have changed due to the removal of the glycosylation, as compared to the previously determined glycosylated HBP structure. Although the primary events in N-linked glycosylation occurs concomitant with polypeptide synthesis and therefore possesses the ability to influence early events in protein folding, we see no evidence of glycosylation influencing the structure of the protein. The root-mean-square deviation between the superimposed structures was 0.24 A (on C alpha atoms), and only minor local structural differences are observed. Also, the overall stability of the protein seems to be unaffected by glycosylation, as judged by the B-factors derived from the two X-ray structures. The flexibility of a glycan site may be determined by the local polypeptide sequence and structure rather than the glycan itself. The biological in vitro activity assay data show that ng-HBP, contrary to glycosylated HBP, mediates only a very limited stimulation of the lipopolysaccharide induced cytokine release from human monocytes. In animal models of fecal peritonitis, glycosylated HBP treatment rescues mice from and an otherwise lethal injury. It appears that ng-HBP have significant effect on survival, and it can be concluded that ng-HBP can stimulate the host defence machinery albeit to a lesser extent than glycosylated HBP.

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Selected References

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  1. Chuang P. D., Morrison S. L. Elimination of N-linked glycosylation sites from the human IgA1 constant region: effects on structure and function. J Immunol. 1997 Jan 15;158(2):724–732. [PubMed] [Google Scholar]
  2. Cumming D. A. Physiological relevance of protein glycosylation. Dev Biol Stand. 1992;76:83–94. [PubMed] [Google Scholar]
  3. Flodgaard H., Ostergaard E., Bayne S., Svendsen A., Thomsen J., Engels M., Wollmer A. Covalent structure of two novel neutrophile leucocyte-derived proteins of porcine and human origin. Neutrophile elastase homologues with strong monocyte and fibroblast chemotactic activities. Eur J Biochem. 1991 Apr 23;197(2):535–547. doi: 10.1111/j.1432-1033.1991.tb15942.x. [DOI] [PubMed] [Google Scholar]
  4. Grabenhorst E., Hofer B., Nimtz M., Jäger V., Conradt H. S. Biosynthesis and secretion of human interleukin 2 glycoprotein variants from baculovirus-infected Sf21 cells. Characterization of polypeptides and posttranslational modifications. Eur J Biochem. 1993 Jul 1;215(1):189–197. doi: 10.1111/j.1432-1033.1993.tb18022.x. [DOI] [PubMed] [Google Scholar]
  5. Heinzelmann M., Mercer-Jones M. A., Flodgaard H., Miller F. N. Heparin-binding protein (CAP37) is internalized in monocytes and increases LPS-induced monocyte activation. J Immunol. 1998 Jun 1;160(11):5530–5536. [PubMed] [Google Scholar]
  6. Heinzelmann M., Platz A., Flodgaard H., Polk H. C., Jr, Miller F. N. Endocytosis of heparin-binding protein (CAP37) is essential for the enhancement of lipopolysaccharide-induced TNF-alpha production in human monocytes. J Immunol. 1999 Apr 1;162(7):4240–4245. [PubMed] [Google Scholar]
  7. Ingham K. C., Brew S. A., Novokhatny V. V. Influence of carbohydrate on structure, stability, and function of gelatin-binding fragments of fibronectin. Arch Biochem Biophys. 1995 Jan 10;316(1):235–240. doi: 10.1006/abbi.1995.1033. [DOI] [PubMed] [Google Scholar]
  8. Iversen L. F., Kastrup J. S., Bjørn S. E., Rasmussen P. B., Wiberg F. C., Flodgaard H. J., Larsen I. K. Structure of HBP, a multifunctional protein with a serine proteinase fold. Nat Struct Biol. 1997 Apr;4(4):265–268. doi: 10.1038/nsb0497-265. [DOI] [PubMed] [Google Scholar]
  9. Iversen L. F., Kastrup J. S., Larsen I. K., Bjørn S. E., Rasmussen P. B., Wiberg F. C., Flodgaard H. J. Crystallization and molecular replacement solution of human heparin binding protein. Acta Crystallogr D Biol Crystallogr. 1996 Nov 1;52(Pt 6):1222–1223. doi: 10.1107/S0907444996010086. [DOI] [PubMed] [Google Scholar]
  10. Jones T. A., Zou J. Y., Cowan S. W., Kjeldgaard M. Improved methods for building protein models in electron density maps and the location of errors in these models. Acta Crystallogr A. 1991 Mar 1;47(Pt 2):110–119. doi: 10.1107/s0108767390010224. [DOI] [PubMed] [Google Scholar]
  11. Karlsen S., Iversen L. F., Larsen I. K., Flodgaard H. J., Kastrup J. S. Atomic resolution structure of human HBP/CAP37/azurocidin. Acta Crystallogr D Biol Crystallogr. 1998 Jul 1;54(Pt 4):598–609. doi: 10.1107/s0907444997016193. [DOI] [PubMed] [Google Scholar]
  12. Kaushal S., Ridge K. D., Khorana H. G. Structure and function in rhodopsin: the role of asparagine-linked glycosylation. Proc Natl Acad Sci U S A. 1994 Apr 26;91(9):4024–4028. doi: 10.1073/pnas.91.9.4024. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Lis H., Sharon N. Protein glycosylation. Structural and functional aspects. Eur J Biochem. 1993 Nov 15;218(1):1–27. doi: 10.1111/j.1432-1033.1993.tb18347.x. [DOI] [PubMed] [Google Scholar]
  14. Lu H. S., Chang D., Philo J. S., Zhang K., Narhi L. O., Liu N., Zhang M., Sun J., Wen J., Yanagihara D. Studies on the structure and function of glycosylated and nonglycosylated neu differentiation factors. Similarities and differences of the alpha and beta isoforms. J Biol Chem. 1995 Mar 3;270(9):4784–4791. doi: 10.1074/jbc.270.9.4784. [DOI] [PubMed] [Google Scholar]
  15. Manneberg M., Friedlein A., Kurth H., Lahm H. W., Fountoulakis M. Structural analysis and localization of the carbohydrate moieties of a soluble human interferon gamma receptor produced in baculovirus-infected insect cells. Protein Sci. 1994 Jan;3(1):30–38. doi: 10.1002/pro.5560030105. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Mer G., Hietter H., Lefèvre J. F. Stabilization of proteins by glycosylation examined by NMR analysis of a fucosylated proteinase inhibitor. Nat Struct Biol. 1996 Jan;3(1):45–53. doi: 10.1038/nsb0196-45. [DOI] [PubMed] [Google Scholar]
  17. Nicholls A., Sharp K. A., Honig B. Protein folding and association: insights from the interfacial and thermodynamic properties of hydrocarbons. Proteins. 1991;11(4):281–296. doi: 10.1002/prot.340110407. [DOI] [PubMed] [Google Scholar]
  18. O'Connor S. E., Imperiali B. Modulation of protein structure and function by asparagine-linked glycosylation. Chem Biol. 1996 Oct;3(10):803–812. doi: 10.1016/s1074-5521(96)90064-2. [DOI] [PubMed] [Google Scholar]
  19. Ostergaard E., Flodgaard H. A neutrophil-derived proteolytic inactive elastase homologue (hHBP) mediates reversible contraction of fibroblasts and endothelial cell monolayers and stimulates monocyte survival and thrombospondin secretion. J Leukoc Biol. 1992 Apr;51(4):316–323. doi: 10.1002/jlb.51.4.316. [DOI] [PubMed] [Google Scholar]
  20. Pereira H. A. CAP37, a neutrophil-derived multifunctional inflammatory mediator. J Leukoc Biol. 1995 Jun;57(6):805–812. doi: 10.1002/jlb.57.6.805. [DOI] [PubMed] [Google Scholar]
  21. Pereira H. A., Erdem I., Pohl J., Spitznagel J. K. Synthetic bactericidal peptide based on CAP37: a 37-kDa human neutrophil granule-associated cationic antimicrobial protein chemotactic for monocytes. Proc Natl Acad Sci U S A. 1993 May 15;90(10):4733–4737. doi: 10.1073/pnas.90.10.4733. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Rasmussen P. B., Bjørn S., Hastrup S., Nielsen P. F., Norris K., Thim L., Wiberg F. C., Flodgaard H. Characterization of recombinant human HBP/CAP37/azurocidin, a pleiotropic mediator of inflammation-enhancing LPS-induced cytokine release from monocytes. FEBS Lett. 1996 Jul 15;390(1):109–112. doi: 10.1016/0014-5793(96)00639-4. [DOI] [PubMed] [Google Scholar]
  23. Rudd P. M., Dwek R. A. Glycosylation: heterogeneity and the 3D structure of proteins. Crit Rev Biochem Mol Biol. 1997;32(1):1–100. doi: 10.3109/10409239709085144. [DOI] [PubMed] [Google Scholar]
  24. Runkel L., Meier W., Pepinsky R. B., Karpusas M., Whitty A., Kimball K., Brickelmaier M., Muldowney C., Jones W., Goelz S. E. Structural and functional differences between glycosylated and non-glycosylated forms of human interferon-beta (IFN-beta). Pharm Res. 1998 Apr;15(4):641–649. doi: 10.1023/a:1011974512425. [DOI] [PubMed] [Google Scholar]
  25. Sareneva T., Cantell K., Pyhälä L., Pirhonen J., Julkunen I. Effect of carbohydrates on the pharmacokinetics of human interferon-gamma. J Interferon Res. 1993 Aug;13(4):267–269. doi: 10.1089/jir.1993.13.267. [DOI] [PubMed] [Google Scholar]
  26. Shafer W. M., Martin L. E., Spitznagel J. K. Cationic antimicrobial proteins isolated from human neutrophil granulocytes in the presence of diisopropyl fluorophosphate. Infect Immun. 1984 Jul;45(1):29–35. doi: 10.1128/iai.45.1.29-35.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Thotakura N. R., Desai R. K., Bates L. G., Cole E. S., Pratt B. M., Weintraub B. D. Biological activity and metabolic clearance of a recombinant human thyrotropin produced in Chinese hamster ovary cells. Endocrinology. 1991 Jan;128(1):341–348. doi: 10.1210/endo-128-1-341. [DOI] [PubMed] [Google Scholar]
  28. Tronrud D. E. Conjugate-direction minimization: an improved method for the refinement of macromolecules. Acta Crystallogr A. 1992 Nov 1;48(Pt 6):912–916. doi: 10.1107/s0108767392005415. [DOI] [PubMed] [Google Scholar]

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